Lab-grown diamonds, a concept first formulated by scientists in the 1950s for use in industrial cutters and polishers, have become an increasingly popular choice for consumer diamonds as well over the past decade.
Whether spurred by ethical concerns surrounding the source of mined diamonds, disavowed of the marketing hoopla of De Beers and its ilk, or merely budget conscious, they can be an attractive alternative.
(Editor’s note: De Beers this week announced it would start selling made-made jewellery at a much lower cost than mined gems.)
Lab-grown diamonds are not fakes, and should not be confused with diamond simulants such as cubic zirconia or moissanite. For all intents and purposes, lab-grown diamonds are chemically identical to their mined counterparts, and cannot be distinguished without the use of specialised equipment.
The only factor that truly separates the two is their formation and this is a factor in the perceived monetary value of lab-grown diamonds, which tend to be less expensive and retain less value than their mined counterparts.
So, how does it work? Tiny slivers of mined diamonds are placed on a special plate and then encased in a chamber utilising high pressure, high temperature (HPHT) methods to mimic the natural crushing process diamonds undergo during formation within the earth.
Sometimes, a process called chemical vapour deposition (CVD) is also used, a process of micro-fabrication that allows carbon atoms in gas to attach themselves in crystalline form to a substrate (in this case, the diamond slivers) using various energy sources, including microwaves, arc discharges and filament. Then, over a period of several weeks, the slivers grow into carbonised black diamonds that can then be cut into their more familiar gem form.
According to the company statement of Brilliant Earth, as American specialist in lab-grown diamonds and other ethically sourced jewellery states that “man-made diamonds are nearly impossible to differentiate from natural diamonds” and that “lab diamonds may exhibit different trace elements than natural diamonds that do not affect the appearance of the diamond.”
However, the retailer is also careful to stress that lab-grown diamonds should come with official certification to show that they have been man-made.
Despite the similarities in appearance, this is not to say diamond miners should be turning in their pickaxes just yet. Through to December 2017, while polished diamonds were down 3.5 per cent, rough diamonds were up 2.7 per cent and De Beers’ full-year sales were up 53 per cent on 2015 figures.
For some, there is more value placed on a diamond than how it looks. Lab-grown diamonds generally retail for 30-50 per cent less than their mined counterparts. There is also an argument made that it is the rarity of a gem that helps it retain its value over time, and over time the cost of producing lab-grown consumer diamonds will fall.
In a recent interview with Harper’s Bazaar, Grant Mobley, a gemologist and owner of major diamond retailer Pluczenik, laid out a few reasons why lab-grown diamonds might not replace mined diamonds, primarily an emphasis on the importance of formation.
Referring to “real” diamonds as unique, rare and “miracles of nature”, he stated:
“Laboratory-created diamonds are stones that mimic the optical and chemical properties of real diamonds, however, they are not formed through natural occurrences—rather they are artificially mass produced in a commercial microwave in a factory in a matter of weeks,” Mobley said.
“The formation of a diamond is one of the attributes that makes them so distinct and rare. Most people have heard that diamonds are made of carbon and form under great amounts of pressure and temperature.
“What tends to be overlooked is how many factors have to align just perfectly for diamonds to form — then, of course, be pushed up to the earth’s surface. It takes anywhere from one to three billion years to form a diamond beneath the earth’s surface.
“Moreover, the formation can only occur in very specific parts of the earth where the combination of temperature and pressure is just right.”
This is, of course, a subjective view, from someone for whom the pursuit and study of diamonds has been a lifelong passion. Others such as Jeffrey D. Feero, managing partner of noted jewellery design company Alex Sepkus, in an interview with the New York Times stated that he didn’t consider most diamonds rare and unusual, “except for rare, natural-coloured diamonds in green, red, pink, purple and vivid yellows”.
Perhaps a sea change will be required for the common-garden groom to change their attitude on lab-grown diamonds despite their nigh-identical chemical makeup, and for now, it seems, the diamond industry is safe.
But in an era where countries such as the Central African Republic, Democratic Republic of Congo and Sierra Leone still wage considerable conflicts over so-called ‘conflict diamonds’, the science is not something to be scoffed at.
This article also appears in the June edition of Australian Mining.